1. Field of the Invention
The invention is directed to a snap fastener suitable for fastening a first thin wall such as a housing wall, door leaf, shutter, or the like, which is provided with a through-opening to a second wall such as a thin-walled wall support such as a housing frame, door frame, wall opening edge, or the like, which is likewise provided with a through-opening, having a base part which can be arranged at the first (or second) thin wall in the through-opening thereof, having a head part extending away from this base part, this head part having in its longitudinal section a diameter which initially increases and then decreases again from the end of the head part in direction of the base part, which head part presents a male plug-in piece which, by overcoming a spring force acting radially outward in direction of the diameter, can be received by an undercut female plug-in piece which is formed by or supported by the through-opening of the thin wall, wherein the head part presents a guide or channel for one or two or more push elements or holding elements which are pressed by at least one spring into a position in which they project over the end of the guide or channel, the ends of which push elements or holding elements projecting out of the guide or the channel have a triangular shape in a projection line extending perpendicular to the thin wall, wherein the base part is formed by a plate overlapping the longitudinal edges of the through-opening in the thin wall, wherein the head part, as a housing, is provided with fastening projections such as fastening cams (of flexible material) or leaf spring devices having flexible fastening surfaces, which housing can be snapped into a through-opening aperture in the thin wall in such a way that it grips only one thin wall (rear panel) and that unlocking devices (releasing means) are provided in the housing, by means of which unlocking devices the push elements can be pulled back into the housing from the front and the housing can be detached from the other thin wall (front panel), wherein the dimensions between the holding area of the fastening projections and those of the push elements on one hand and the support plane of the base part on the other hand are selected in such a way that the fastening projections lie upon the front panel with play when the push elements are pulled back.
2. Description of Related Art
A snap fastener of the type mentioned above is already known from WO 2008/128560.
A drawback in the prior art consists in that when fastening one wall part to another wall part with a plurality of snap fasteners of the type mentioned above, it is difficult to bring the snap fasteners simultaneously into the position that makes it possible to remove one wall part from the other wall part.